Coil for electrical purposes and method of producing same.



E. A, DE WOLF.

COIL FOR ELECTRICAL PURPOSES AND METHOD OF PRODUCING SAME.

I AIPLIGATION FILED APR.15, 1913.

1,091,046. Y Patented Mar. 24, 1914,

Z SHEETS-SHEET 1.

ATTORNEYS E. A. DE WOLF.

PURPO AND METHOD LEI) APE.15 1

' COIL I 'OB ELECTRICAL 0F PRODUCING SAME.

APPLIOATIO v 91s. I

v Patented Mar. 24, 1914 I 2 SHEETS-"SHEET 2.

WITNESSES 4 Mi; 02in UNITED STATES PATENT OFFICE;

ERNEST A. DE WOLF OF MANSFIELD, MASSACHUSETTS, ASSIGNOR T JOSEPH ROBERT LEESON, OF BOSTON, MASSACHUSETTS.

COIL FOR ELECTRICAL PURPOSES AND METHOD OF PRODUCING SAME.

To aZZ 1011,0212 it may concern Be it known that I, ERNEST A. DE \Vorir,

. a citizen of the United States, residing at Mansfield, in theco-uuty of Bristol and Gommonwealth of Massachusetts, have invented certain new and useful Improvements in Coils for Electrical Purposes and Methods of Producin Same, of which the following is a specification.

simple matter to guide the winnings or con- My invention relates to coils for electrical purposes, such as magnet and resistance coils, and to an improved method of pro- Specification of Letters Patent.

ducing the same.

It consists particularly of a novel system of winding wire or other conducting material in layers of adjacent helices andsimultaneously winding insulating mate'riaL-s-uch as yarn orthread, contiguous the ends of the wire layers to build up-abutments for holding the wire windings from displacement and to provide protecting heads or flanges at the ends of the coil.

The object of my improvement is to dispense with the usual spool or support on which electrical coils are commonly wound, while at the same time producing a finished coil in which the convolutions are properly disposed and securely held in exact relation lack of uniformity to each other and so protected at the ends that the windings'will not be displaced in handling or through rough usage.

The invention isfully described in the following specification, illustrated by the accompanying drawings, in which like letters of reference designate like parts.

. In the drawings: Figure l is a side elevation of my improved coil; a

longitudinal. sectional view of the tube or core on which the coil is wound, showing a few layers of windings in place; lfi 3 is an elevation of a portion of the winding device used for winding the coils, showing the arrangement and relation of the windingguides and their rccil'n-ocating means; Fig.- 4 is an end elevation of the same.

It is the usual practite in winding electrical coils to build the wire up on spools or similar supporting means having end heads or flanges which are designed to hold the windings from displacement and prevent' the convolutions from drawing down or. falling over the cnds'of the coil. In winding coils by hand it is a comparatively chanically-controlled winding.

ported the y? relations of the wire close up to the inner l Patented Mar. 24, 1914. Serial No. 761,286.

faces of the spool flanges before leading For various reasons, however, such as economy in cost of production and greater accuracv, and precision in laying the turns of wire. it has been found expedient to produce the coils by mechanical means rather than through manual operations. In winding coils by machine one difficult-y encountered has been to provide a guiding device which ,vill direct the wire close up to the supporting heads at the ends of the spool. In order to make the guiding device effective for the precise laying of the coils it is necessary that its delivery point he maintaii'ied surface on which the windings deposited. i-N ow, since the guide must have a width or thickness the thickness of the wire, it is obvious that it cannot be arranged to reciprocate between the heads of the spool without a clearance at'each end which renders it practically impossible to lay the Wire close up against the inside faces of the heads.

Another obstacle to the accomplishment of perfect winding by machine arises from the in thickness or diameter of the wire ei'nployed and variations in the length of the spools. It is a well known fact that insulated wire cannot be made in long lengths of absolutely uniform diameter and, furthermore, it is practically impossible in manufacturing the coil-support mg spools in quantityv to make them uniformly of the same length between the heads. Owing to this variation in diameter of the wire the different layers in the coil cannot be made of uniform lengthwhen they arewouiul with the same number of turns in each layer, which is necessary in me- In addition to this, the varlationsin the length of the spools cause further discrepancies as regards regulating the length of the wire layers to correspond exactly with the distance between the spool heads For these reasons it is practically impossible to adjust the winding sothat the ends of all of the layers will come exactly flush with the inner faces of the spool heads to provide for their being sup consequently, some of the benefit for which the spool is designed is lost. lVhere' the length of the layer is shorter than the distance between the spool heads the individual convolutions of wire are being close to the materially greater than are liable to separate or spread out and in some cases the spaces between the turns will be so'wide that the windings of subsequent layers, wound on top, will be forced down into the interstices to cause defects in the completed coil. Where the windings tend to fill a longer space than that allowed between thespool heads-the convolut-ions or turns of the wire will be crowded. so that they pile one on another and this also results in uneven layers and irregularities in the winding which act to diminish, and in some cases'toentirely destroy, the electrical efi'iciency of the coil. have been devised to overcome these dithculties, but so far these have not been entirely successful and it is a difficult matter at the present time-t0 wind perfect coils by machine. In some cases the guide for the wire has been arranged to reciprocate in a path outside the edges of the heads of the spool, but this method is open to serious defects, particularly in winding coils of large diameter. Under these conditions, the delivery point of the guide being a considerable distance from the core on which the first layers of windings are deposited, it is almost impossible to control the disposition of the turns accurately and at some points they will be too far separated while at others the windings may pile on each other and form ridges and hollows. It is most important that the turns or convolut-ions of the coil be accurately and precisely laid in relation to each other as otherwise the in ductive and conductive elfect of the current is interfer d with or entirely lost, and hence the electrical etliciency of the coil is impaired. Frequently this eificiency may be entirely destroyed and it is often necessary to discard the completed coil owing to a single defect in the winding.

In my present invention I propose, to

build up the supporting and protecting flanges at the ends of the coil coincident and concurrently with the building up of the layers of wire windings. during the winding of each layer of wire effect a simultaneous winding of insulating material. such as thread or yarn, to build up a mass of the same thickness closely abut ting the ends of the wire layer. The winding proceeds in this way until the desired diameter is reached and when the coil is completed it will have two opposite abutments consisting essentially of disk-like formations of yarn supporting and protecting its ends. Thse abutments, being of relatively soft, resilient material, are adapted to. conform to irregularities in. the ends of the wire layers and hence they are more effective for the purpose usual rigid spool heads. layers of yarn or ings are elastic That is to say, the

Various expedients That is to say,

designed than the other supporting wind-i to a considerable extent and adapt themselves to the more rigid wire windings so as to fill up all interstices at the ends of the coil and provide a selfsustaining,

responding exactly with the ends of the layers of wire windings. To make the abutments more stable and permanent they may be coated with shellac, glue or other plastic material, or immersed in a bath of plastic rubber or cement which solidifies the structure and amalgamates the yarn windings with the wire windings.

The manner of carrying out my invention is as follows: Referring to the drawings, the coil C preferably wound on a tube a: of paper, fiber or other similar material, or it might be built up on any suitable core, either of cylindrical, polygonal or other form. The wire to is laid with the usual spool wind having the turns or helices disposed closely adjacent each other and built up in layers Z, Z, etc., as shown most clearly in Fig. During the winding of the wire I. simultaneously effect the winding of the yarn y at both ends of the coil with the yarn layers building up in the same ratio as the wire windings. In order to insure that the yarn may be built up in self-sustaining disk-like formations having substantially the well-known universal or \l-wino ystem for this portion of the coil. This method of winding results in a very stanch and stable structure even when the yarn is wound with a relatively short traverse. As illustrated in the drawngs the end abutments of the coil, which are virtually narrow, disk-like cops of yarn or thread, have a thickness, taken longitudinally of their axis, of about one-sixth the length of the wire layers. That is to say, the two end abutments of yarn. windings occupy about one-fourth the whole length of the coil, but these proportions are not arbitrary and can be varied to suit different conditions. For instance, in a coil of less diameter, where there would be less constrictive tendency of the windings and less liability of the wire convolutions becoming misplaced or disarranged, the yarn coil could be made thinner.

In order to make the s *stem of winding my improi'ed coil more readily understood I have shown the essential elements of the winding apparatus or machine in Figs. 3 and i of the drawings. Referring thereto, I; designates the guide for the wire 1:0, and (Z and c the guides for the thread or yarn y. The wire-guide Z)- is mounted at the end of a traverse-rod which carries a slide or runner at its opposite end having a stud or roll /2 projecting fron'i its under side to engage the groom ,5 in the traverse-cam J Th yarn- -uides (Z and c are both mounted on a traverse-rod 7.: at a distance apart equal self-conforming abutment, cor-- liSkS at the ends of the 'llO "may be erse tothe'yarn-guides (Z and 6.

to the length of traverse of the guide Z). The rod 71: carries a slide at provided with a roll or stud n which engagesthegroove 0 in the traverse-cam O. Thecams J and O: mounted on the same shaft or onseparate shafts and Qfas illustrated in" Fig. 3, and" are arranged torotate independ: ently of each other] The camJ is operated to give a relatively slow traverse to the wire-guide Z) 'whilethe'cam O is driven at a faster rate to impart a short, quick 'trav- Referring to Fig. 4, the guide b pivots on the traverse-v rod 7 toallow it to swing outwardly from the axis of the tube w, as .the'wire is built. up thereon, while the guidesd and e are pivoted on the rod Z0 and move-back from the tube as the yarn windings increase in diameter. Means, not hereshown, are also provided for maintaining the guides hearing on the surfaceof the winding. It will be understood that the tube a: is held on a suitable winding-spindle or mandrel, not here illustrated, which rotates in the direction indicated by the'arrow 2, Fig. 4.

Referring to Fig. 3, the wire-guide-b traverses along the tube in from r to s to wind the wire layers Z, see Fig. 2; while the yarnguide (Z traverses from t to 1" and the guide e from s to u to build up the yarn cops or 'fore provides for greater electrical efliciency and less liability of other defects. In addition, the end abutments of the-coil are self-conforming, as previously explained, and adapt themselves exactly to the requirements of the wire vwindingssothat an improved supporting and retaining effect is secured. At thesame time the completed coil is much morestable and permanent on'account of the substantialend abutments which act as a protecting and cushioningmeans-to prevent damage to the windings .in handling or when in use. The end abutments of my improved coil might bewound from materials other than yarn, such as silk thread,similar attenuated fibers, or with narrow, fiat tapes. Other modifications might be made in the material or arrangement of the windings, particularly as to variations in dimension and form, without departing from the spirit or scope of the present invention; therefore I do not limit myself to the exact embodiment shown and described.

What I claim herein is:

1. A coil for electrical purposes composed of a series of layers of conducting material built up with substantially fiat ends, and abutments of insulating material wound in the form of disk-like cops and built up-adabutments Y and Y. Any other equivalent. arrangement might be used for reciprocating the several guides, and suitable means, not here shown, are provided to control the ratio of speed between the winding-spindle jacent said ends to support and protect the windings of the coil.

2. A coil for electrical purposes comprising a series of layers of conducting material, and windings of insulating material built and the guides to effect the proper disposition of both the wire turns and the yarn windings. The size of the yarn or other insulating material used for the end abutments Y, Y depends on the size of the wire being wound and is determined by the thickness of the several layers required to equal one layer of wire. This proportion is easily found by experiment and usually a fine yarn is employed, the drawings showing its size somewhat exaggerated in order to illustrate the windings more clearly.

From the above explanation it will be understood that my new system of winding enables me to build up a coil with protecting end abutments which take the place of the usual retaining heads or flanges of the spools commonly used for this purpose. The abutments or yarn disks Y, Y are built up coincident with the building of the coil; that is. with the same ratio of growth or increase in diameter. It will therefore be seen that the guide for the wire can be arranged to bear constantly on the surface on which the windings are being deposited, without interference from the end flanges, and hence the convolutions or turns can be more accuup adjacent the ends of said layers and dis posed with a cross-wind to form self-sus- 'taining disk-like abutments for supporting and protecting the ends of the coil.

'3. In a coil for electrical purposes, the combination with a series of layers of wire wound with closely adjacent helices, of two series of layers of yarn wound with a diagonal or cross-wind to build up, disk-like cops abutting the ends of the wire layers and serving to support and protect the ends of the coil.

4. An improved method of manufacturing electrical coils consisting in winding wire in layers of adjacent helices and simultalayers abutting the ends of-the wire layers to build up self-sustaining and self-c0nforming disk-like flanges adjacent the ends of the coil.

5. An improved system of winding electrical coils consisting in winding a conducting material on a core, with a traverse of predetermined length and simultaneously winding an insulating material with a diagonal or cross-wind at the ends of the core with a traverse of relatively less length to of the turns of wire in the coil and therebuild up abutments for supporting and protecting the ends of the coil.

short circuiting or neously winding yarn with a cross-wind in 6. An improved system of winding electrieal coils consisting in -a core in layers 01': a given length and at winding Wire oni the same time winding yarn with adiagonal or cross-wind at the ends ot the wire layers with a relatively short traverse to build up supporting abutments at the ends of the coil eoincidingln growth with the growth of the :core with a relatively slOW wire windings. v

An mproved system of winding electrical e s consisting in winding wire on a. traverse and at the same time winding yarn on the core with a diagonal wind having a relatively 'quiek traverse to build up abutment's adjacent the ends of the wire layers coincident with the growth in diameter of the latter.

S. An improved system of windmg electrical coils consisting in guiding the wire on to the core with arelatively slow traverse and concurrently guiding yarn on to the core with diagonal eonvolutions having a. relatively short, quick traverse at points edjacent both ends of the wire layers to build up supporting and protecting abutments for the ends of the coil.

In testimony whereof I atfix my signature in presence of two witnesses.

ERNEST A. DE WOLF.

Witnesses HERBERT E. KING, CHARLES N. CRANE. 

